Furnace



oct. 29, 1929. f. c. sHERwoon 1,733,561

FURNACE Filed Jan. 12, 1928 3 Sheets-Sheet 1 0ct. 29, 1929. T. c. sHERwooD FURNACE Filed Jan. 12, 1928 5 Sheets-Sheet 2 Patented Oct. 29, 1929 e UNITED srarrI-:sl

PATENT `ol-Frcrz TBUMAN c. sIrIiRwoon, or nANvILLca'ILLINoIs, AssIGNoR'ro sIIEnwoon SANITARY y FURNACE constrain,v INoonroRarEn or nANvILLn, ILLINOIS Y i FURNACE' Applicationledanuary 12, 1928.y Serial No. 246,109.

This invention relates tofurnaces, and more particularly 'to hot air furnaces, having for its object the rprovision of a novel construction and arrangement whereby the draft supply for combustion is furnished yby the air withdrawn from thek building;` and also the provision of means` for taking the draft air out of thereturn air in the furnace.' i

A further object is to provide a hot air furnace which is simple in construction, economicalv in fuel/consumption, and more sanitary and eicient lthan furnaces'heretofore used.

y Otherobjects will appear hereinafter.

The invention consists in the combination D andy arrangement of parts hereinafter described and claimed. t j i y, f

Theinvention will behest understood by reference to the accompanying j drawings forminga part of this application and in whichm,k f' g Figurel'y is a frontelevation of' the fur'- nace, also showing the-airpipes communicating with parts'of thebuilding; v t

yFigure 2l isa vertical sectional viewtaken on theline 2-12 of Figure 1; f y

Figure 3 isa cross sectional view taken on the line. 3;-3 of Figure 2; y

Figure 4 is a facevievv ofy the air intake baiilelplate.. I i 4 As illustrated inthe drawings, the preferred embodiment comprises an outer casing 12 and an inner shell 13 appropriately spaced to provide air chambers 14. Leading from the upper portion of the outer casing 12, are hot air outlet pipes llvwhich communicate with various part-s of the buildingfor conveying theheated air. Intake pipes 16A prefer ably lead from the first floorof the 'building tothe lower portion `oftheouter casing 12, as. shown in Figure 1.I An auxiliarypipe 17 communicates from the outside of the building to one of the intake. pipes 161,A and is pro,- vided with a suitablel damper 1S. Similarly they outlet pipes k have dempers 1 9disposed therein for controlling `and regulatinggthe volume of heated air passing into the buildi ing; A grate `frame 20 rests upon suitable angle irons 21 and supports the grate bars 22. The fire box 23 is lined with re brick 24 in the usual mannen, and communicates with a smokepipe 25'by means of the smoke outlet pipe 26, and adjacent the opening into pipe 26, agbafle member 27, semi-spheroidal in shape, restsin shoes 28. f

On each side of the furnace, and preferabl disposed in line with the pipes 16,' are dra t doorsy29 hingedly mounted upon projecting collars 30, and the draft doors 29 areconnected by rods to levers 31 whichextend be-L yond thefront of the furnace and provide for regulation ofthe' ydraft by adjust-ment ofthe draftdoorsto any desired position.

The ash door 32 is not provided with the usual hinged draft door, or slide draft but is cast in one piece tor make a tight closure. The fire door 33 is provided with the usual small adjustable air inlet 34 for admitting air above the fire, and a vapor pan 35 is ordinarily supplied with water for moistening the all'. i 1

Inorder to uniformly distribute the air .draft supply beneath the grates, a distributor plateaBG, supported by brackets 37 is positioned at each side ofthe furnace, opposite the draft doors and is` yprovided with diagonallyextending ribsI 38 and also with ports 39 for directing and distributing the air draft;` y f n y InA operating the furnace the ash door 32 remains closed' and the entire draft supply enters through the draft openings 30, whic communicate directly Wit-h the air chamber 14. Infthis manner the relatively cool air withdrawn from the' building throu h the pipes 16y is nsed in part to supplyr a raft for the tire, yand the'remainder is heated by contact with the inner shell 13 as it moves upwardly inthe chamber 14, and it is then conveyed to the various parts of the building by pipes 1,5. "Under ordinary conditions no additional air supply for draft purposes is required, but to meet exceptional conditions, additional air may be supplied by opening the damper 18 in the auxiliary pipe 17. The regulator 34 in the fire door admits the desired quantity of air above the fire to promote combustion.

In they preferred embodiment illustrated, the furnace shell 13 is oval-shaped in cross section to afford greater contacting surface for the incoming air. By utilizing the withdrawn air as a draft supply, lint, dust and various impurities. in the .air are gradually withdrawn from the interior of the building andvthus the furnaceris more sanitary than existing'types.

It will be apparent to those skilled in the art, that the described principle of operation may be adapted toa furnace of the so-called pipeless type by making such changes as the difference in structural form requires.

f While'I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modication without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details" of construction setrforth, but desire to avail 'myself of such Vvariations and modifications as come within the scope'of the appended claims. f

Having described'my invention, what I claim asfnew and desire to secure by Letters PatentV is:

1. In a hot air furnace, an inner shell, an outer4 casing, an air chamber between said shell and casing, air outlet pipes leading from said outer casing and adapted to convey heated air to the various parts of a building for heating purposes, air intake pipes leading from the heated portion of the building rto which said outlet pipes are connected, said intake pipes communicating with said outer casing, grates mounted within said shell, and a'draft inlet to said shell positioned below the grates and opening directly into said air chamber but not communicating; otherwise ywith the exterior of the furnace, whereby air k'for draft purposes is supplied by said air intake pipes. f I

2. In a hot air furnace, an inner shell, an outer casing, an air chamber between said shell and casing, air outlet pipes leading from said outer casing and adapted to convey heated air to the various parts of Va building for heating purposes, air intake .pipes lead,- ing from `the heated portionrof the building to which said outlet pipes are connected, said intake pipes communicating with said outer casing, grates mounted within said shell, a draft inlet to said shell positioned below the grates. and opening directly into said air chamber but not communicatingotherwise with the exterior of the furnace, whereby air for draft purposes is supplied by said air intake pipes, and means for directing and distributing the draft air currents.

3. In a hot air furnace, an inner shell, a outer casing, an air chamber between said shell and casing, air outlet pipes leading from said outer casing and adapted to convey heated air to the various parts of a building for heating purposes, air intake pipes leading from the Iieated portion of the buildingl to which said outlet pipes are connected, said intake pipes communicating with said outer casing, grates mounted within said shell, a draft inlet to said shell positioned below the grates and opening directly into said air chamber but not vcommunicating otherwise with the exterior of the furnace, whereby air forY Vdraft purposes is supplied by said air intake pipes, and a baiiie plate provided with air ports for directing 'anddistributing the draft air currents.

4. In ahot air furnace, an inner shell, an outer casing, air outlet pipes leading from said outer casing and adapted to convey heated air to the various parts of a building for heating purposes, air intake pipes leading from the heated portion of the building to which said outlet pipes are connected, said intake pipes communicating with said outer casing, grates mounted within said shell, a draft inlet to Ysaidshell positioned below the grates and opening directly into said air chamber but not communicating otherwise with the exterior of the furnace, whereby air for draft purposes is supplied by said yair intake pipes, and means for regulating the volume of air admitted through said draft inlet. 5. In a hot air furnace, an inner shell, an o utercasing, an air chamber between said shell and casing, air outlet pipes leading from said outer casing and adapted to convey heated air vto the various parts of a building for heating purposes, air intake pipes leading from the heated portion of the building to which said outlet pipes are connected, said intake pipes communicating with said outer casing, grates mounted within said shell, a draftinlet to said shell positionedjbelow the grates and opening directly into said air chamber but not ,communicating otherwise with the exterior of the furnace, whereby air for draft purposes is supplied by said air intake pipes, means for directing and distributing the draft aireurrents, and means for regulating the volume of air'admitted through'said draft inlet.

Y 6. In a hot air furnace, an inner shell, an outer casing, an air chamber between said shell and casing, air outlet pipes leading from said Vouter casing and adapted to convey heated air to the various parts of a building for heating purposes, air intake pipes leading draft inlet to said shell positioned below the grates and opening `directly into said air chamber but not communicating otherwise with the exterior of the furnace, Whereb air for draft purposes is supplied by sai air intake pipes, a bale plate provided with air ports for directing and distributin the draft air currents, and kmeans for regu ating the volume of air admitted through said draft inlet.

In testimony whereof I have signed my name to this specification.

TRUMAN C. SHERWOOD. 

